[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

From |
wgould@stata.com (William Gould, StataCorp LP) |

To |
statalist@hsphsun2.harvard.edu |

Subject |
Re: st: Precision for locals? |

Date |
Wed, 12 Aug 2009 10:44:33 -0500 |

Sergiy Radyakin <serjradyakin@gmail.com> asked, > what is the precision with which the locals are stored in Stata? and Maarten Buis <maartenbuis@yahoo.co.uk> replied, > A discussion of this can be found in (Gould, Pitblado, and > Sribney 2003) page 83: "Macros provide about 12 digits of > accuracy, sometimes more but never less. Scalars are full > double-precision binary numbers, meaning they provide about > 16.5 digits of accuracy in all cases" The first sentence of what we wrote in 2003 should be updated to read, Macros provide about 12 digits of accuracy, sometimes more, but nevel less than 11. As Kit Baum noted, often macros provide about the same as a double, for example, . local x = sqrt(2) . display "`x'" 1.414213562373095 Here is an example with 12 digits, . local x = sqrt(2)*10^20 . display "`x'" 1.41421356237e+20 Here is an example with 11 digits: . local x = sqrt(2)*10^102 . display "`x'" 1.4142135624e+102 -- Bill wgould@stata.com * * For searches and help try: * http://www.stata.com/help.cgi?search * http://www.stata.com/support/statalist/faq * http://www.ats.ucla.edu/stat/stata/

- Prev by Date:
**st: multiple colors in twoway plots** - Next by Date:
**Re: st: RE: Sargen-Hansen and instruments--RE vs. FE** - Previous by thread:
**Re: st: Precision for locals?** - Next by thread:
**st: -meta- command: how do I change the background color of the forest plot from black to white?** - Index(es):

© Copyright 1996–2017 StataCorp LLC | Terms of use | Privacy | Contact us | What's new | Site index |